1. Field of the Invention
The present invention relates to a method and apparatus for manufacturing paper cushioning members, and more particularly, to a method and apparatus for cutting a single sheet or plural sheets of work paper to be processed, such as unused paper or unnecessary newspaper, used copying paper, paper printed by an OA (Office Automation) equipment or used corrugated cardboard, to plural rows of thin intermittently-cut bands, stretching the resultant sheet or sheets of work paper to form a net, and crumpling the net-like sheet or sheets into an air-containing ball which has an adequate softness to thereby ensure continuous mass-production of such paper balls and permit the use of the paper balls as cushions or packings for transporting objects.
2. Description of the Related Art
There are cushions made of synthetic resin, which are to be placed between transporting objects and a box to protect the transporting objects against any damage. To avoid any pollution problem, however, there are paper cushions used for the same purpose instead of the synthetic-resin cushions. The simplest type of the paper cushions is a sheet of newspaper crumpled into a ball or paper torn to pieces which are then crumpled, or a corrugated cardboard cut into pieces as an intervening material depending on the usage.
Another known cushion is a strong kraft paper processed to have short cuts and link portions by press working and then stretched to yield a fine almost beehive-like net.
Of those paper cushions, the first type, namely balls made of newspaper, involve a troublesome work and are likely to vary in quality. Although the torn and crumpled pieces of paper, the second type, are soft to serve as good cushions, they are independent piece by piece and are easy to scatter, resulting in a lower working efficiency. In addition, since it is difficult to use the torn and crumpled pieces of paper directly, they are normally placed in a paper bag or a poly bag when in use. If the bag is torn or broken, however, the crumpled pieces of paper undesirably come out of the bag through the torn section.
Although a corrugated cardboard, when cut to pieces, ensure an even thickness, those pieces are still hard and are not so suitable as cushions.
With regard to the pressed kraft paper or the last type of cushion, when the processed kraft paper is stretched, a fine beehive-like net is formed due to the cuts and link portions. When the net is crumpled, soft and spongy feeling to some degree would be attained. Due to the press working, however, the processing size of a single sheet of kraft paper is limited and it is not possible to simultaneously process plural sheets of kraft paper. Further, as the resultant net is finely formed, the horizontal stretching ratio is small, so that the net, when crumpled into a ball, contain less air. Furthermore, as the link portions are short, the link portions are easily cut when stretched unless the kraft paper is very strong. Tn addition, as the net is finely formed, the material should be a thin sheet of paper and the net should be formed sheet by sheet.